Electric vacuum pumps?

[choptopbII]

Currently doing a cummins swap on a 68 gmc truck with vacuum brakes... And as you know the cummins does not have a vacuum pump. So I'm wondering if it would be worth it to go with an electric vacuum pump or not even messing with that and converting to a hydro boost setup. Don't really have a whole lot of experience with this so forgive me if I sound stupid. Haha thank you guys.

 

[Rot Box]

My last two Cummins had vacuum pumps. Unless I'm mistaken they're located right in front of the power steering reservoir on the 12v and 24v engines (not sure about common rail). That said Hydroboost is a popular swap on both the early Dodge/Cummins and Fords of the day for better braking performance.

 

[choptopbII]

Forgot to mention I will be towing with this truck (likely just my Toyota and 36 Chevy) so nothing crazy... are the vacuum brakes even safe ? Will it stop okay? I feel stupid asking this stuff

 

[choptopbII]

I honestly haven't even pulled the motor out of my donor truck yet. I was told I would need a vacuum pump to run the brakes. But could be mistaken.... Might just swap to hydro boost anyways. Seems to be the safer option.

 

[Rot Box]

A friend of mine plumbed the Cummins vacuum pump into his booster on an 82 Chevrolet. It works fine but it makes this weird loud whirling sound when he presses the brake petal. Not sure if it was something he screwed up or not..

The early Cummins and Ford diesels used vacuum pumps for their brakes. Hydroboost seems to be a popular swap for those who haul heavy. My Ford uses vacuum brakes and it doesn't bother me with a single vehicle on a car hauler.. Much more than that I'd probably look into hydroboost.

Hope this helps.

On second though maybe my 2nd gen used Hydroboost and the 1st gen used vacuum... I don't remember.

 

[choptopbII]

Donor truck is a 94, and I'm pretty sure it's hydro boost I'll have to go look at it. It'd currently burried under 2 feet of snow. I guess I just need to weigh out my options haha but thank you for the help I really appreciate it.

 

[rockdog]

Umm, shouldn't you be out putting that rear axle under that 36?

 

[boogie_4wheel]

The vacuum pump is mounted to the back of the PS pump. You will need to add an vacuum accumulator tank to increase the capacity; could be super simple and make one out of some PVC pipe. The pump alone wont be enough to run the brake booster.

Have you thought about swapping to discs on the 68, at least on the front? I think that would be more important than going from vacuum to hydro on the booster.

 

[choptopbII]

Umm, shouldn't you be out putting that rear axle under that 36?��

Oh its all in. I got all the suspension finished. haha Ill post some pictures here soon. Its come a long way!

 

[choptopbII]

The vacuum pump is mounted to the back of the PS pump. You will need to add an vacuum accumulator tank to increase the capacity; could be super simple and make one out of some PVC pipe. The pump alone wont be enough to run the brake booster.

Have you thought about swapping to discs on the 68, at least on the front? I think that would be more important than going from vacuum to hydro on the booster.

I'm doing a 1 ton axle swap on it so it will be discs in the front and drums in the back. But Thank you for the information! Really helpful guys.